Libertarianism when applied to the social and political structure of technology and open source (Meritocracy) perpetuates inequality by failing to acknowledge the role of power and current state of inequality.
American libertarianism is uniquely American, unfortunately Silicon Valley happens to be in America. It is a political and social philosophy that believes individual ownership and power should supplant collective ownership of any kind. Most immediately the ownership and interventionist powers of government should be dismantled and the free market should be left with the responsibility of creating equality and individuals expected to protect their own interests.
Filtered through the lens of technology this becomes a more unified theory of Meritocracy. For our purposes here, it is no coincidence that meritocracy ends with -ocracy, like many other hierarchy-oriented words such as autocracy, aristocracy, kleptocracy, mobocracy and plutocracy.
Being that we don't trade goods for currency we don't have a traditional market and libertarians must invent one. A strange mix of experience, social capital, and skill are a sort of currency in technology communities. Meritocracy is the social theory that allows that currency and its exchange to become power the way actually currency becomes power in a capitalist free market.
This is where techno-libertarians and people attempting to build a system of equality collide. To build a more equitable system you have to re-distribute power. If there is an imbalance of race and gender (there obviously is) then it means the under-represented are not engaged and have no power under the existing standards of "merit." To alter representation we must alter the process and culture of technology creation to subvert the value of "merit" so that people without it can engage.
Of course, meritocracy has a good side, as meritocratic policies (perhaps distinct from meritocracy as an "emergent" phenomenon) has in some cases enabled recognition of working class people and other social underdogs through institutions contrived to be status-blind, at least in theory, such as civil service exams, hands-on career training in the military, college financial aid, affirmative action and the like. On the other hand, meritocracy also has an -ocracy side that reinforces hierarchy. This side of meritocracy affects the world of software in ways that go well beyond questions of money. [Meritocracy can be and has been a barrier to entry even into unpaid work in noncommercial open-source projects.](http://anagory.wordpress.com/2012/02/28/why-im-not-ready-to-jump-on-the-p2p-bandwagon/ A blog post by n8chz on the growing sentiment that being even an unpaid programmer is not an entitlement)
Attempting to alter existing gender or race imbalance is always in conflict with libertarian meritocracy because being black or female has no currency in the system they've created. Such a system must be called out for what it is: a process of subjugation that perpetuates existing power structures. Existing power happens to be white male dominated. Libertarians would then argue that the fact that existing power is white male dominated does not mean the system itself is racist or sexist because the system doesn't value race or sex, only "merit." Of course, Libertarians don't devalue race or sex either, but again, since they don't devalue existing power either (as long as it's "private" power, anyway) it can only be inevitable that social capital and other advantages accrued in whatever is seen as a pre-libertarian order means some people are effectively grandfathered in to the hopefully libertarian order, as opposed to being, in very profound ways, on the outside looking in.
To all of this advocates of equality must respond that any system which perpetuates historical racism and sexism inherits those traits by willful ignorance.
Libertarianism is the philosophy of non-intervention. That no system should exist which attempts to mitigate the private exchange of currency, goods and services in a free market. Any intervention, even intervention that would create gender or racial equality, cannot be tolerated without admitting that the free market is a poor arbiter of freedom.
In the birth of a new culture where a market and currency do not exist as they do elsewhere libertarianism invents the tyranny of meritocracy so that we might extend even further the domination of those who have inherited power over those who currently lack it. If we are to create a more equitable culture we must reject it.